Conventionally, there has been a perfector disclosed in Patent Literature 1.
The perfector disclosed in Patent Literature 1 includes: a blanket impression cylinder and a blanket cylinder being in contact with each other and configured to perform printing on both surfaces of a paper sheet; inking units configured to supply inks to the blanket impression cylinder and the blanket cylinder and supported to be movable toward and away from the blanket impression cylinder and the blanket cylinder; and transporting means for holding and transporting the printed paper sheet to a delivery unit. In the perfector, the transporting means is formed of: a first delivery chain extending below the inking units; first to third transfer cylinders configured to transport the paper sheet from the first delivery chain; and a second delivery chain configured to transport the paper sheet from the first to third transfer cylinders. Moreover, the perfector includes: a checking camera configured to detect a printing condition on one surface of the paper sheet transported by the first transfer cylinder; and another checking camera configured to detect a printing condition on the other surface of the paper sheet transported by the second transfer cylinder.
In this perfector, it is regarded that, since a quality check of both surfaces is performed in-line in a period between the printing on both surfaces and the delivery, there are no increase in installation space and no increase in the overall length of the perfector.